Most petroleum well pumping systems utilize some form of gas and sediment separator. The most common separator is referred to as a mud anchor or a conventional “poor boy” separator such as shown in FIGS. 1 and 2. The performance of this simple design is adequate for most low volume wells.
More complex related art varies from static designs with multiple chambers (U.S. Pat. No. 6,336,503), baffles (U.S. Pat. No. 6,179,054) or spiraling cascades (U.S. Patent Application No. 2001/0004017), to dynamic designs with rotating turbines (U.S. Pat. No. 6,283,204 and U.S. Pat. No. 6,155,345). The more complex art is designed primarily to address gas problems in high volume wells. Whereas the present invention is designed to submerse casing perforations in fluid enriched with produced oil, if the prior art is configured such that the casing perforations are submersed, then annular fluid will be enriched with produced water.
Prior art oil production apparatus designed to control the coning of formation water near the wellbore and to separate oil and water downhole utilize configurations where the oil and water zones are both perforated, with the oil zone being perforated at the top of the reservoir formation and the water zone being perforated at the base of the reservoir, and with an unperforated interval between the two sets of perforations. The oil is pumped from above the upper perforations, while the water is pumped from below the lower perforations, either with an open wellbore (U.S. Pat. No. 6,196,312) or with an isolation packer set between oil perforations and water perforations (U.S. Pat. No. 6,131,655 and U.S. Pat. No. 6,125,936). Whereas the present invention provides the following functions, none of the prior art provide submersion of the entire perforated interval in oil or provide the option of slowing the fluid production rate with the hydraulic head of a predetermined oil column, none of the prior art described in Section [0004] include components for gas and sediment separation.